CROSS JOIN vs INNER JOIN in SQL Server

CROSS JOIN:

SELECT 
    Movies.CustomerID, Movies.Movie, Customers.Age, 
    Customers.Gender, Customers.[Education Level], 
    Customers.[Internet Connection], Customers.[Marital Status], 
FROM   
    Customers 
CROSS JOIN 
    Movies

INNER JOIN:

SELECT 
    Movies.CustomerID, Movies.Movie, Customers.Age, 
    Customers.Gender, Customers.[Education Level], 
    Customers.[Internet Connection], Customers.[Marital Status]
FROM   
    Customers 
INNER JOIN 
    Movies ON Customers.CustomerID = Movies.CustomerID

Cross join does not combine the rows, if you have 100 rows in each table with 1 to 1 match, you get 10.000 results, Innerjoin will only return 100 rows in the same situation.
These 2 examples will return the same result:

Cross join

select * from table1 cross join table2 where table1.id = table2.fk_id

Inner join

select * from table1 join table2 on table1.id = table2.fk_id

Use the last method

Here is the best example of Cross Join and Inner Join. Consider the following tables TABLE : Teacher x------------------------x | TchrId | TeacherName | x----------|-------------x | T1 | Mary | | T2 | Jim | x------------------------x TABLE : Student x--------------------------------------x | StudId | TchrId | StudentName | x----------|-------------|-------------x | S1 | T1 | Vineeth | | S2 | T1 | Unni | x--------------------------------------x 1. INNER JOIN Inner join selects the rows that satisfies both the table. Consider we need to find the teachers who are class teachers and their corresponding students. In that condition, we need to apply JOIN or INNER JOIN and will Query SELECT T.TchrId,T.TeacherName,S.StudentName FROM #Teacher T INNER JOIN #Student S ON T.TchrId = S.TchrId SQL FIDDLE Result x--------------------------------------x | TchrId | TeacherName | StudentName | x----------|-------------|-------------x | T1 | Mary | Vineeth | | T1 | Mary | Unni | x--------------------------------------x 2. CROSS JOIN Cross join selects the all the rows from the first table and all the rows from second table and shows as Cartesian product ie, with all possibilities Consider we need to find all the teachers in the school and students irrespective of class teachers, we need to apply CROSS JOIN. Query SELECT T.TchrId,T.TeacherName,S.StudentName FROM #Teacher T CROSS JOIN #Student S SQL FIDDLE Result x--------------------------------------x | TchrId | TeacherName | StudentName | x----------|-------------|-------------x | T2 | Jim | Vineeth | | T2 | Jim | Unni | | T1 | Mary | Vineeth | | T1 | Mary | Unni | x--------------------------------------x